Railway traffic controlling apparatus



July 7, 1931. 1.. E. SPRAY RAILWAY TRAFFIC CONTROLLING APPARATUS Filed001:. 9, 1929 2 Sheets-Shea! 1 INVENTOR! lhEs July 7, 1931, E. SPRAYRAILWAY TRAFFIC CONTROLLING APPARATUS Filed Oct. 9, 1929 2 Sheets-Sheal-2 v/ {Q INVENTOR;

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Patented July 7, 1931 UNITED STATES PATENT OFFICE LESTER E. SPRAY,'WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH 62, SIGNALCOMPANY, OF'SWISSVA JLE, PENNSYLVANIA, -A CORPORATION 01 PENNSYLVANIARAILWAY TRAFFIC conraonmivo rrnnhrus Application filed October 9, 1929.Serial no. 398311. a

contacts 137, 112, 51, 135, 56,1523 152 and i a My invention relates torailway trafiic controlling apparatus, and particularly to apparatus forcontrollinga switch and the signals which govern traffic movements overthe switch by means carried on a railway vehicle.

I will describe one form of apparatus embodying my invention, and willthen point out the novel features thereof in claims.

The accompanying drawings, Figs. 1 and 2, when placed end to end withFig. 1 on the left, constitute a diagrammatic view showing one form ofapparatus embodying my invention.

Referring to the drawings, the reference characters, 1 and 1 designatethe track rails of a stretch Y of railway track over which tratlic maymove in either direction, and which is connected with a siding Z bymeans of a switch W. Rails 1 and 1 of stretch Y are divided by means ofinsulated joints 2 into sections AV-B, B -C, C-,D, DE and Each of thesesections is supplied with current by a battery .3 connected across therails adjacent one end of the section, and is provided with a trackrelay which is designated by "the reference letter with a distinguishingexponent and which is connected across the rails adjacent the oppositeend of the section.

Signals designated by the reference characters S S S and S",respectively, govern the movement of trailic over switch VV,-signals Sand S directing eastbound trafiic, that is, trafiic moving toward theright, as

shown. in the drawings, and signals S -and S? directing Westboundtraffic. Signals S and S govern traffic movements along stretch Y overswitch 1V in its'normal position,as shown in the drawings, whereassignals S and S govern traffic movements along stretch Y to or fromsiding Z over switch W reversed. Each of the signals, as shown in thedrawings, is of the semaphore type.

Switch W can be operated by any suitable means, such, for example, as anelectric motor M havingan armature 148 and a field winding 154 as shownin the drawings.

W Qperatcd in conjunction with switch W a e 141. Of these, contacts 51and 56 are closed when switch W is in itsnormal position only; contacts137, 135 and 141 are closed when switch W' is in its reverse positiononly; contact 112 is closed when switch Wis in either its normal or itsreverse position only; contact 152 is closed at all times except whenswitch W is reversed; and contact 1 52* is closed at all times exceptwhen switch V is in its normal position.

' Motor M is controlled by a polarized switch relay N, thedirection ofenergization of which iscont'rolled by a polarized stick relay P. RelayN is also controlled by contacts 9.5, 96, 98 and 99 which are operatedby the arms of signals S S S and S respectively, and each of which isclosed onlywhen its signal arm is in the stop position.

The energization of relay P in the normal direction by its pick-upcircuits is controlled by back contacts of a neutral stick relay T, andthe -rencrgization of relay P in the reverse direction is controlled byfront contacts of relay T.

One pick-up circuit for relay T is :controlled by track relay G and byan auxiliary stick relay K. The energization of relay K is controlled bytrack relay G and by an inductor device L which is located in thetrackway adjacent the end F of section E-.-F. Inductor device L is: inturn controlled by'a' vehicle carried inductor device Inductordevice Lcomprises two windings, 72 and 74, on a U-shaped core 73 of a magneticmaterial. Winding 72 is connected in series with thewinding of relay K.Inductor device J comprises a winding 160 011 a U-shaped core;161 of amagnetic material. The ends of winding 160 are connected togetherthrough a manually operable push button contact An approach relay R iscontrolled by front contacts of relays Gr and G Acsecond approach relayR is similarly controlled by front contacts of relays G and G Adirectional stick relay 1" is provided with a pickup circuit whichiscontrolled by front cont cts of relays G nd It A no i ill

trolled by back contacts of'r' relays G and G and a. second stickcircuit for relay r is controlled by a back contact of relay R Relay Tis provided with a second pick-up circuit which is controlled: by amanually operable push button contact U located adjacent signal S Thearms of signals S S S and S have two positions indicating proceed andstop, respectively. Signals S S S and S are selectively controlled bypolar contacts of relay P when switch V is in a position which agreeswith the direction of energization of relay P. 1

By means of a control lever V, switch W can, in emergency, bedisconnected from motor M and connected to a manually operable lever notshown in the drawings. Lever V has two positions, a and t. When lever Vis in its n position, switch WV is connected to motor M, and when leverV is. in its 6 position, switch W' is connected to the manually operablelever. Lever .V is equipped with four contacts, two of which, 101 and44,'are closed when lever V is in its a position only, and the other twoof which, 143 and 139, are closed when lever Vis in its t position only.lVhen lever V is moved to its trposition, the circuit for relay N isopened at contact 101 of lever V, and the control circuits for signals SS S and S through contacts of relay P, are opened at contact 44 of leverV. By means of contacts 143 and 139, signals S ands may be cleared whenswitch 1V is in its reverse position while lever V is in its '15position. "Contact 44 prevents the clearing of eithersignal S orS whenswitch 1V isin itsn'ormal position while lever V is in itst position: 1I

As shown in the drawings, energy is supplied to the various parts of theapparatus by" batteries designated by the reference character Q, withdistinguishing exponents; Having thus described, in general, thearrangement and location of the various parts'comprising my invention,Twill now trace the operation of'the apparatus. I

As shown in the drawings,"all parts are in their normal condition, thatis, all'track sections. between A and F are unoccupied,

" switch 1V is in its normal position, and signals S and S areindicatingproeeedij With the track sections-unoccupied, all relays G areenergized.

F.1Vith relays G and G energized, relay R l is energized by its circuitpassing from battery Q through wire 24, contact 25 of relay G wires 26and 27, contact 28 of relay G wire 29, winding of relay R, and wires 30,and 30 back to battery Q3. With relay R energized, relay 1' is energizedby the circuit just traced for relay ,R as far as wire 26, thencethrough contact 31 of relay R, wire 32, winding of relay 1, and wire 30to wire 30 I lVith relays G and G energized, relay R is energized by itscircuit passing' from battery Q through wire 33, contact 34 of relay Gwire 35, contact 36 of relay G wire 37, winding of relay R and wires 30,30 and 30 back to battery Q With relay R energized, relay r is energizedby the circuit just traced for relay R as far as wire 35, thence throughwire 38, contact 39 of relay R wire 40, winding of relay T and wire 30to wire 30*.

\Vith relays r and r energized, relay P A is energized bya normalpick-up circuit passing from battery QP, through wires 4, 4 and 4contact 5 of relay 1 wire 6, contact 7 of relay 7", wires 8,10 and 11,contact 12 of relay T, wires 13 and 14, winding of relay P, wire 15,contact 16 of relay '1, wires 17 and 18, contact 20 of relay 9', wire21, contact 22? of relay 7' and Wires 23 and23 back to battery Q Withrelay P energized in its normal direction, the arm of signal S is heldin its proceed position by its circuit passing from battery Q throughwires 4 and'4 contact 41 of relay G wires 42 and 43, contact 44 of leverV, wire- 45, contacts 46 and-47 of relay P, wire 48, contact 49 of relayB, wire 50, contact 51 of switch \V,"wire 52, the mechanism of signal Sand wire 23 back to battery QR: The arm of signals is held in itsproceed position by a circuit including the circuit just tracedfor'signal S as far as wire 48, thence through wire 53, contact '54 ofrelay R wire 55, contact 56 of switch WV, wire 57, the mechanism ofsignal S and wires 23 'and 23 -back to battery Q lVithrelay G energized,relay K is energized by its' pick up circuit passing from battery Q},through wire 24, contact 71 of relay G winding of relay K, winding 72 ofinductor-L; and wire 30 back to battery- Q A stick circuitfo'r relay Kis also closed, including the pickupcircuit just traced for relay Kexcept passing around contact 71 ofrelay Githrough wire 75, and contact76 of relay K.

finding 74 of deviceL is constantly energized byits circuit passing frombattery Q}, through wires 24 and 24,'-winding 74,'and wire 30 back tobattery Q}. i a

Inductor device J is shown with thet erminals of its winding 160connected together through push button contact U.

I will now'assume that a westbound train, carrying an inductor device J,,enters section E--F, de-energizing relay which, by its contact 25, inturn de-energlzes relays R and 1'. With relay 1' de-energized a branchpath is closed around contact 7 ofrelay 1" in the circuit previouslytraced for relay P, this branch path passing from wire 6, throughcontact 7 of relay 7, wire 86, and contact 9 of relay G to wire 10. Asecond branch path is also completed around contact 20 of relay 1 in thecircuit previously traced for relay P this branch path passing from wire18, through contact 19 of relay G", and contact 20'" of relay 1* to wire21. The cir-' cuit for signal S is opened at contact 49 of relay It, andhence the arm of signal S moves to its stop position,

I will assume further that while the train is carrying device J overdevice L contact U, carried on the train is left closed, With contact Uclosed while device J ispassing over device L winding 160 opposes thepassage of magnetic flux through core 161 of device J from core 73 ofdevice L; The in crease of magnetic flux passing through core 73 due toproximity of the core 161 is therefore not great enough toinduceanelectro motive force in winding'm of such a magnitude, inopposition to battery Q as to cause relay K to open its front contacts;

As the train proceeds further and enters section DE de-energiz'ing relayG the Sec ond pickup circuit previously traced for relay P is openedatcontacts 9 and 19 and a normal stick circuit is completed for relay Ppassing from battery Q through wires 4,- 4 and 49, contact 5 of relay rwire 6, contact 7 'oa relay r, wire 86*, contact 9 of relay G wire 87,contact 88 of relay G wire 90, contact 159 o'f rel ay P, wire 14:,winding of relay P,-cont'act-158 of relay P, wire 157, contact- 156 ofrelay G wire 15;), contact-19 of relay G contact of relay 1*,- wire 21,contact 22* 013 relay 7' and wires 23 and 23 back to battery Q 1 Thetrain upon entering section de' energizes relay G which then opens, atits contacts 88 and 156 the stick circuit just traced ,fo-r' rel-ay' P.i A pick-up circuit for relay P is their closed following the stick icircuit just traced for relay P except passing from wire 87 thence tlirougl-r contact 88"" of relay G wire 11*, contact 1'2 of relay T',-

wires 13' and 14 win-ding of relay P, "wire 1 5, contact 16 of relay'13, wire 1 7 and contact 1 56 of relay G towire 155 Relay G uponbecoming de'-energi'z'ed opens, at its contact 41 the circuit ma ma-sthe-arm of which thereupon moves to -its stop posi tion \Vhen thetrainleaves section ID -E; per-' m'itting relay G to again become energized,-relays R1 and- 1" are agai-n energized by their circuits previouslytracedc With: relay energizefithe pick-up circuit last traced for relayPisropened at contactsa'l and-:26 of relay 1' and the pick-up circuitfirst traced for relay P is again closed.

As the train enters section BC de-energizing relay G, a stick circuitfor relay 1" is completed passing from battery Q or, through wires58,58, 5a 58 and 58 contact 108 of relay R wires 109 and 110, contact111 of relay r winding of relay 1, and wires 30 30 and 30 back tobattery Q.

When the train leaves section C D, relay 1 continues energized by itssecond stick circuit, and relay continues energized by its pick-upcircuit first traced. Also when the trainleaves section C-D, the arm ofsignal isoperated to" its proceedposition by its circuit previouslytraced. 7

the trainleaves section'A-B, relay R again becomes energized by itscircuit previously traced, and the arm of signal S is operated to itsproceed position by its circuit previously traced.

I will now assume that with all parts again in their normal condition, awestbound train enters section E'F, and that while a device J, whichcarried on this train, is movingioyer device L, the push button contactU, carried on the train,- is held open. The magnetic flux passingthrough core 73- is thereby suddenly increased due to lowered reluctanceof its magnetic circuit on account of the proximity of the" core 161.

On account of the de-energization of relay '1 G by the train enteringsection E- F, relays R- and '1 are again de-energized as alreadydescribed; Relay R upon becoming deeencrgized opens, at its contact 49,the circuit' for signal S, the arm of which then moves to its stopposition.

Upon the de-energization of relay K, re-

lay T becomes energized by its pick-up" cir cuit passing from batteryQ}, through wires 24 and'Z5-,contact 76 of relay K, contact 77 of relayG wire 78, contact 79' of relay G wire 80, winding of relay T, and wires30, 30 and 30 back to battery Q Relay T upone closing its contact 83completes its stick circuit passing from: battery Q through i? Relay Gupon becomingdcwires 58, 58 and58", contact 81 of relay G wire 82,contact 83 of relay T, wire 84, winding of relay T, and wire 30 back tobattery Q via Qj. Relay T upon becoming energizedreverses the polarityof the current flowing through the winding of relay P by the secondpick-up circuit described for relay P. Relay P thereupon operates itspolar contacts to the reverse position, opening at its contact 47 a thecircuit for signal S the arm of which then moves to its stop position.

lVith the reverse polar contacts of relay P closed, and with all signalsindicating stop, relay N becomes energized in the reverse direction byits circuit passing from battery Q through wire 23, winding of relay N,wire 104, contact 103 of relay G wire 102, contact 101 of lever V, wire100, contact 99 of signal 8 contact 98 of signal 3*, wire 97, contact 96or signal S contact 95 of signal S wire 94, contacts 93 and 92 of relayP, and wires 91 and 91 back to battery Q}. The reverse operating circuitfor switch N is now closed passing from battery Q through wires 4 and 4contacts 145 and 150 of relay N, wire 149, armature 148 ofniotor M, wire147, contact 146 of relay N, wire 123, contact 152 of switch WV, wire153, field winding 154 of motor M, and wires 91 and 91 to battery Q viaQf. Switch W is thereupon operated to its reverse position. Contact 152is opened just before the completion of this movement ofswitch W,thereby opening the motor circuit.

When switch W is reversed, a circuit is completed for signal S passingfrom battery Q through wires 4 and 4, contact 41 of relay G wires 42 and43, contact 44 of lever V, wire 45, contacts 46 and 47 of relay P, wire134, contact 141 of switclr-N, wires 142and 144, mechanism of signal S,and wires 23 and 23 back .to batteryQP. The arm of signal S then movesto its proceed position, opening its contact 98 and therebyde-energizing relay N. Relay T continues energized by its stick circuit,previously traced, and hence relay P continues energized in the reversedirection by its circuit already described, while the train is insection EF.

lVhen the train enters section D.E, a reverse stick circuit iscompletedfor relay P passing from battery Q}, through wires4, 4 and 4,contact 5 of relay 1, wire 6, contact 7 of relay 1", wire 86, contact 9of relay G wire 87, contact 88 of relay G wire 90, contact 159 of relayP, winding of relay P, wire 14, contact 158 of relay P, wire 157,contact 156 of relay G wire 155, contact 19 of relay G, contact 20 ofrelay 1, wire 21, contact 22 01 relay 7, and wires 23 and 23 back tobattery Q When the train enters section C- D deenergizing relay T byopening the stick circuit for relay T, a normal pick-up circuit is againcompleted for relay P, through contacts88 and 156 of relay Gr aspreviously traced. At the same time, relay G opens, at its contact 103,the circuit for relay N which is thereupon de-energized. With relay NClo-energized because of the opening of contact 103 of relay G thenormal energiza'tion of relay P does not cause relay N to be energizedin its normal direction, and hence switch W continues in its reverseposition until the train moves out of section CD. On account of relay Pbeing energized in its normal direction, signal S does not clear whenthe train leaves section CD, and hence relay N now becomes energized inits normal direction by its circuit passing from battery Q through wire4, contacts 92 and 93 of relay P, wire 94, contact 95 of signal Scontact 96 of signal S wire 97, contact 98 of signal S, contact 99 ofsignal S wire 100, contact 101 of lever V, wire 102, contact 103 ofrelay G wire 104, windiiig of relay N, and wire 23 back to battery RelayN now being energized in its normal direction, motor M is operated byour rent flowing in the normal direction through its circuit passingfrom battery Q through wires 4 and 4, contacts 145 and 146 of relay N,wire 147, armature 148 of motor M, wire 149, contact 150 of relay N,wire 151, contact 152? of switch W, wire 153, field winding 154 of motorM, and wires 91 and 91 to battery Q via Q Upon the completion of theoperation of switch W to its normal position, the arm of signal S isagain operated to its proceed position. Thereupon relay Nbecomesde-energized by the opening of contact 95 ofsignal's I will next assumethat, with all parts again in their normal condition, a train on sidingZ is to proceed into stretch Y over switch W. In order to reverse switchW for this trafiic movement, a trainman closes contact U If neither aneastbound nor a westbound train is approaching in stretch Y, relays 1'and 1 are energized, and hence upon the-closing of contact U relay T isenergized by asecond pick-up circuit which passes from battery Q,through wires 8 and 58 contact U wire 127, contact 128 of relay 1", wire129, contact 131 ofrelay 7, wires 132 and 80, winding of relay T, andwire 30 back to battery Q. Relays r and 1' would also be energized if aneastbound train were moving awayfrom switch W, except under a conditionwhich will hereinafter be explained or if a westbound train were movingaway from switch W, and hence relay T would then also be energized bythe closingof contact U It follows therefore that a train approachingfrom either direction in stretch Y would prevent the control of switch Wby push button U1, but that? a recedingtrain would have m tact l ofrelay- P, and the arms of these Upon the energization of relay T bycontact U relay P becomes energized in the reverse direction due to thereversal of polarity of the current supplied to the winding of relay Pthrough its pick-up circuit first traced. The control circuits forsignals S and S are therefore opened at consignals then move to the stopposition. R6- lay N then becomes en'ergized'in the reverse direction bythe circuit already traced through contract 92 of relay P, causingswitch W to be operated to its reverse position. With switch IV in its.reverse position, signal S* will be cleared by its circuit alreadytraced, and signal S? will be cleared by its circuit which follows thecircuit already traced for signal S*, as far as wire 134, thence throughcontact 135 of switch W, wire 136, mechanism of signal S and wire 23back to battery Q hen the train enters section C-D,- relay G by openingits contact 41, breaks the circuits for signals S and S which will thenindicate stop. Relay T becomes deenergized by the breaking of its stickcircuit at contact 81 of relayGr and hence relay P is energized in thenormal direction as first traced.

l Vhen the train enters section D-E, a stick circuit is closed for relay1" passing from battery Q through wires 58, 58, 58 and 58 contact 116 ofrelay G, wire 117, contact 118 of relay G wires 1'19 and 120, contact121 of relay 1, winding of relay 7*, and wires 30, 30" and 30 back tobattery Q; Also when the train enters section D- E, relay It becomesd'e-energized due to the opening of its circuit by contact 28 of relay GWith relay R tie-energized a second stick circuit is completed for relay'1" pass ing from battery Q}, through wires. 58, 58", "58 and: 58contact 112 of switch-WV, wire 113, contact 11 1 of relay R, wires 115and 120, contact 121 of relay r; winding of relay 1*, andswires30 30 and30 back to battery Then the" train leaves section CD, relay G? becomesenergized and; completes the normal control circuit for relay N. Relay(Du accountof thecontrol otthe second stick circuit for relay 1"bycontact 112 of switch W, relay 7* becomes de-energized when a trainreceding from switch W' after having moved over switch W in its reverseposition. On account of this arrangement, if a train, after moving outof siding Z, should stop east of signal S while preparing to reverse itsdirection of movement and to proceed westward over switch W normal,another train could not, upon entering the east end of section E"'F,c'au'se switch W to be reversed while the train adjacent signal S isstarting to move westward.

I will now assume that with all parts again in their normal condition, awestbound train enters section E'F,-and with its contact U openpassesover inductor L causing relayT to be energized, and relay T then causingrelay P to be energized in the reverse direction. I will also assumethat at the time relay P becomes energized in the, re verse direction,an eastbound train enters section AB, de energizing relay 7-. Relay Pthen continues energized in the reverse direction by a stick circuitpassing from battery Q through wires- 4,- 4 and 4,- con? tact 5 f relay1' wires- 85 and 87', Contact 88 of relay G wire 90, contact 159 ofrelay P, winding of relay P', wire 14, conta'ct1 58 of relay P, wire157,- contact- 156' or relay G wires" 155 and 124, contact 2 2 of relayW, and wires 23 and 23 back to battery Q With relay P energized in thereverse di rection, relay N also becomes energized in the reversedirection although; the eastbound train has entered section A- -B';Switch W is then operated to its reverse position by motor I willnextassume that with all parts again intheir normal cenditi'on aneastbound train enters section A-''B, de-ener'giz--' ing relay W, I willalso assume that a westbound train thenenters section E'-F, and withits-contact U open, passesover inductor L causing relayTtobecome-energi'zed. The eastbound train, by de ener'g'izing" relay 7*has already opened the pick-up-cir'cuit for" relayP at contacts 5and-22i?oftrelay T and has closed a normal stick circuit for relay Pthrough contacts 5" and 22 of relay 1. Hence the westbound train, it itdoes not energize relay T until after the eastbound train hasd'e-ener'gized relay 9, cannot cause switch WV tobe operated to-it'sre'verse" position;

I will now assume that on account-of some emergencysuc'h, for example,as a failure of motor M, it is necessary to reverse switch by hand foratrain-te move to or from siding Z1 A trainman will therefore' reversecontrol lever V to itst position th'ereby dis-F connecting switch W-trommotor and connecting it"to' themanuall'yoperable lever; When lever'V isreversed, the control circuits for signak S and S are opened at contact44 of lever V, and hence the arms of signals S and S fall to their stopposition. Upon the completion of the movement of switch IV to itsreverse position by the manually operable lever, signals S and S will beoperated to their proceed position, an operating circuit for signal Snow passing from battery Q through wires 4 and 4, contact 41 of relay Gwire 42, contact 137 of switch WV, wire 138, contact 139 of lever V,wires 140 and 136 mechanism. of signal S and wire 23 back to battery Q Asimilar operating circuit for signal S follows the path just traced forthe circuit for signal S as far as wire 138, thence through contact 143of lever V, wire 144, mechanism of signal S, and wires 23 and 23 back tobattery Q After the train has passed switch WV, a trainman will returnswitch IV to its normal position by the manually operable lever, but thearms of signals S and S will not'clear until lever V has been returnedto its 12 position.

From the foregoing description and from the accompanying drawings, it isclear that my invention provides approach locking for a railway switchof the type which is controlled by apparatus carried on a movingvehicle. My invention also provides .for clearing of signals governingover the switch when provision exists for operating the switch by handand while the switch is in its reverse position, but prevents theclearing of signals governing over the switch when the provision existsfor operating the switch by hand and while the switch is in its normalposition.

Other systems embodying subject matter disclosed but not claimed hereinare disclosed and claimed in a copending patent application of commonownership, Serial- No. 658,540, filed August 21, 1923, by Bertram R.Padmore, for railway switch controlling apparatus, and in a copendingpatent application of common ownership, Serial No. 696,436, filed March3, 1924, by Harry E. Brashares, for protected switch operating system.

Although I have herein shown and described only one form of railwaytraflic controlling apparatus embodying my invention, it is understoodthat various changes and modifications may be made therein within thescope of the appended claims without departing from the spirit and scopeof my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track containing a switch,trackway means for controlling the operation of said switch when avehicle approaches said switch, means for preventing such operation ofsaid switch when a second vehicle moves toward said switch but not whensaid second vehicle moves away from said switch, and means forcontrolling said trackway means from said first vehicle.

2. In combination, a stretch of railway track containing a switch,trackway means for controlling the operation of said switch when avehicle approaches said switch from a given direction, means forpreventing such operation of said switch when another vehicle is movingtoward said switch from a different direction, and means carried on saidfirst vehicle for controlling said trackway means.

3. In combination, a section of railway track containing aswitch,'trackway means for controlling the operation of said switch whena vehicle approaches said section from a given direction, means forpreventing such operation of said switch when another vehicle is movingtoward said section from a different direction, and means carried onsaid first vehicle for controlling said trackway means.

4. In combination, a stretch of railway track including a section whichcontains a switch, trackway means for controlling the operation of saidswitch when a vehicle occupies said stretch in a given direction fromsaid section, means for preventing such operation of said switch when asecond vehicle occupies said stretch in a different direction from saidsection, and means carried on said first vehicle'for controlling saidtrackway means.

' 5. In combination, a stretch of railway track containing a switch,vehicle carried means for controlling the operation of said switch whenthe vehicle approaches said switch from a given direction, means forpreventing such operation of said switch when a second vehicle is movingtoward said switch from a diflerent direction, and means for permittingsuch operation of said switch when said second vehicle is moving awayfrom said switch. a V

6. In combination, a stretch of railway track containing a switch,vehicle carried means for controlling the operation ofsaid switch whenthe vehicle approaches said switch from a given direction, and means forpreventing such operation of said switch when a second vehicle is movingtoward said switch from a different direction. v

7. In combination, a stretch of railway track containing a switch,vehicle carried means for controlling the operation of said switch whenthe vehicle is in said stretch in a given direction from said switch,and means for preventing such operation of said switch when a secondvehicle is in said stretch in a difierent direction from said switch.

8. A railway switch controlling system comprising a power operatedswitch having first signal when such provision exists for manualoperation of said switch, and means for clearing said second signal whensaid switch is in its reverse position while such provision exists formanual operation of said switch.

9. In combination, a stretch of railway track containing a switch, aneutral stick relay, trackway means for controlling a pick-up circuitfor said stick relay, a stick circuit for said stick relay controlled bytrafiic conditions within said stretch of track, railway Vehicle carriedcontrol means for controlling said trackway means, a polarized stickrelay, a normal and a reverse pick-up circuit for said polarized stickrelay controlled by said neutral stick relay, a normal and a reversestick circuit for said polarized stick relay controlled by trafiicconditions within said stretch of track, and means controlled by saidpolarized stick relay for controlling said switch.

10. In combination, a stretch of railway track containing a switch, apolarized stick relay, trackway means for controlling a normal and areverse pick-up circuit for said stick relay, a normal and a reversestick circuit for said stick relay controlled by trafiic conditionswithin said stretch of track, vehicle carried means for controlling saidtrackway means, and means controlled by said stick relay for controllingsaid switch.

11. In combination, a stretch of railway track containing a switch, aneutral stick relay, a pick-up circuit for said stick relay controlledby manually operable means, a stick circuit for said stick relaycontrolled by traffic conditions within said stretch, a polarized stickrelay, a normal and a reverse pick-up circuit for said polarized stickrelay controlled by a back and a front contact respectively of saidneutral stick relay, a normal and a reverse stick circuit for saidpolarized stick relay controlled by traffic conditions within saidstretch, and means controlled by said polarized stick relay forcontrolling said switch.

12. In combination, a stretch of railway track comprising a first and asecond section, a track switch for said first section, means foroperating said switch, a stick relay, a pick-up circuit for said stickrelay controlled by traflic conditions in said second section, a stickcircuit for said stick relay controlled by a contact which is closedwhen and only when said switch is in one or the other of its extremepositions, and means controlled by said stick relay for controlling saidswitch.

In testimony whereof I aflix my signature.

LESTER E. SPRAY.

